Heat-resisting casing



(Model.)

T. A. MACDONALD. HEAT RESISTING GAS'ING.

Patented Apr 29, 1884.

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i UNITED STATESv PATENT OFFICE.

THOMAS A. MACDONALD, OF BOSTON, MASSACHUSETTS.

HEAT-RESISTING OASING.

SPECIFICATION forming part of Letters Patent No. 297,613, dated April 29, 1884.

i Application filed JuneklB, 1883. (Model.)

To all whomv t may con/cern.- Be it known that I, THoMAs A. MAoDoN- ALD, a citizen of Canada, residing at Boston,

.in the `county of Suffolk and State of Massay chusetts, have invented a new and useful Improveinent in Heat-Resisting Oasings, of which the following is a specification.

The object of my invention is to produce an efcient, durable, and comparativelyinexpen- A represents a piece of ordinary stift` card-V board of any required thickness. .On one side of the card-board I attach a thin layer or sheet of asbestus by means of any suitable cement or adhesive substance not affected by heat. The paper-board and asbestus are then subj ected to a powerful pressure by means of rollers,whereby thetwo component parts becomeV rmly united. .The article is to be used as a casing for indirect radiators in connection With steam and hot-water heating apparatus. It is also used as a hotair conductor, it being f sufficiently exible to be formed into tubes.

It can be made in large sheets, and, if the sheets are not suficiently large, two or more can be joined together, as required. It can also be cut with shears to adapt it to any desired position or connection. The asbestus lining, being toward the heating-surface of the apparatus of which it forms the easing, protects the paper or cardboard from injury, and the two form an excellent non-conducting material of heat.

Thin wood which is used as a casing is liable to Warp and shrink, which objections my invention is free from.

Sheet-iron is liable to rust, which cannot be said of my invention, and is not so good a nonconductor of heat as the material above described, ,constituting my invention.

My invention is Ydesigned to be made and sold in sheets as anew article of manufacture.

I am aware that asbestus has been used as a covering `for `furnaces, & e. 5 but this I donot claim.

What I claim as my invention, and desire to secure by Letters Patent, is-

A non-radiating casing forindirect radiators and hot-air radiators, composed of card-board and asbestus united together by an adhesive substance and subjected to pressure, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification in the presence of twoV subscribin g witnesses. THOMAS A. MACDONALD. Witnesses: v

J. H. ADAMs, E. PLANTA. 

